Hot-gas reciprocating engine



Nov. 4, 1952 H. DE BREY ETAL HOT-GAS RECIPROCATING ENGINE Filed Jan. 12,1950 6 9 C O 0 0 0 0 O 0 0 0 00 0O 00 0O O m %O O O O O O 000 0 U zT DRYEB HB CM MA NL FRANCISC AGENT Patented Nov. 4, 1952 HOT-GASRECIPROCATING ENGINE Heinrich de Brey and Franciscus Lambertus vanWeenen, Eindhoven, Netherlands, assignors to Hartford National Bank andTrust Company, Hartford, Conn., as trustee Application January 12, 1950,Serial No. 138,134 In the Netherlands January 27, 1949 3 Claims. (01.60-24) This invention relates to hot-gas reciprocating engines.

A hot-gas reciprocating engine is known in which the hot and cold spacesassociated with a thermodynamic cycle and arranged in two differentcylinders are in open communication with each other through a heater, aregenerator and a cooler. Further particulars concerning hotgasreciprocating engines are to be found in Philips Technical Review,volume 8, page 129 et seq. and volume 9, page 97 et seq. and page 125 etseq.

The object of the invention is to provide an improved hot-gasreciprocating engine in that by suitable combination and relativearrangement of the heater, regenerator and cooler the resist ance toflow of working medium of the engine through the elements is reduced andit is furthermore possible for the heater and the cooler to be built upfrom very simple components. In addition, when employing the invention,the combustion chamber of the engine is suitably defined.

The engine according to the invention exhibits the feature that the tubeheater, regenerator and tube cooler, which are arranged immediatelyafter one another, are in line with one another and the tubes of theheater are arranged in one or more coaxial rings and thus define thecombustion space of the engine.

Due to the fact that the heater, the regenerator and the cooler are inline with one another, the resistance to flow of the medium of theengine through these elements is but low. The said three elements may beunited to form a single unit with the use of simple constructionalmembers, in which tube material is a factor of importance, said unitbeing adapted to be fitted on the engine cylinders by means of transferpassages. Due to the fact that the tubes of the heater define thecombustion space of the engine they ensure not only satisfactory heattransfer from the combustion gases and the flame of the burner to thesetubes but also a simple construction of the furnace wall proper, sincethe pipes of the heater protect this wall from excessive heating.

According to a preferred embodiment of the invention, the tubes of thecooler are also arranged in one or more coaxial rings so as to besubstantially in line with the tubes of the heater and they arepreferably housed in a cooling agent container. Particularly thefirst-mentioned measure has the effect of further reducing theresistance to flow f the medium through the heater, regenerator andcooler.

If, in accordance with an alternative embodiment of the invention, theregenerator is annular and its inner and outer diameters are very nearlyequal to the inner and outer diameters of the zone in which the heaterand cooler tubes are opened out into the regenerator space, it isensured that the path to be traversed by the working medium of theengine in the heater, regen erator and cooler is substantially straight.

In order that the invention may be more clearly understood and readilycarried into effect, it will now be described more fully with referenceto the accompanying drawing in which:

Figure 1 shows a preferred embodiment of a hot gas engine according tothe invention;

Figure 2 shows a cross-sectional view of the heater taken along the lineII-II in Figure 1, and

Figure 3 shows a cross-sectional view of the cooler taken along the lineIIIIII of Figure 1.

Figures 1-3 show one embodiment of a hotgas engine according to theinvention, which comprises two cylinders and 8!, the longitudinal axesof which are at right angles to each other. The pistons 82 and 83 arelinked by a common crank to a crank shaft 84. The space 85 above thepiston 82 in cylinder 80 constitutes the hot space of the thermodynamiccycle performed in the engine and the space 86 above the piston 83 incylinder 8| constitutes the cold space associated with that cycle. Thecylinders 80 and BI are provided with transfer passages 81 and 88 whichare separated by a heater 89, a regenerator 90 and a cooler 9|, whichare integral with one another. The heater 89 comprises tubes arranged incoaxial rings, a cavity 92 being defined within the inner ring. Thiscavity acts as a combustion space for the burner 93. The tubes 89 areintermediate the combustion space and the furnace wall 94 so that thiswall is not subjected to high temperatures and may be of very simpleconstruction. The regenerator 90 is annular, the central aperture beingsealed by a body 95 of refractory material. The cooler 9| also comprisestubes arranged in coaxial rings and is contained within a wall 96. Thesetubes are substantially in line with the tubes of the heater, so thatthe resistance to flow of the medium is extremely low. The space withinthe wall 96 and without the tubes contains cooling-water suppliedthrough a duct 91 and discharged through a duct 98. An extremely simpleengine is thus obtained.

What we claim is:

1. A hot-gas reciprocating engine having a closed thermodynamic cycle,comprising a first said heater being: formed by a plurality of tubesarranged incoaxial rings with an open central combustion space.

2. A hot-gas reciprocating engine having a closed thermodynamic cycle,comprising a. first cylinder enclosing a hot space. a second cylinderenclosing a cold space, means connecting said hot and cold spaces, atubular heater,,tubu1ar cooler and regenerator arranged in line in saidmeans, said heater being formed by a plurality of tubes arranged incoaxial rings with an open centralv combustion space and said cooleralso having" a plurality of tubes formin coaxial rings which aresubstantially in line with said tubes in said heater.

3. A hot-gas reciprocating engin having a closed thermodynamic cycle,comprising a first cylinder enclosing a hot space, a second, cylinderenclosing acold space, means connecting said hot and cold spaces, atubular heater, tubular cooler and regenerator arranged in line in saidmeans, said heater being formed by a plurality of tubes 4 arranged incoaxial rings with an open central combustion space, said cooler alsohaving a plurality of concentric tubes forming coaxial rings which aresubstantially in line with said tubes of said heater, and saidregeneratcr being formed by-an annular body located between the'tubes ofsaid heater and said cooler with a refractory member in the centralaperture of the annular regenerator body to minimize heat transfer fromsaid" central combustion space to said cooler.

HEINRICH DE BREY.

FRANCISCUS LAMBERTUS VAN WEENEN.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 155,087 Hirsch .r Sept. 15, 1874228,716 Woodbury et al. June 8, 1880 334L153 Babcock eases-.111 Jan. 12,1886 991,989 Holm, a May 9, 1911 1,613,038.- Koenig, Jan. 4, 192?2,326,901, Thompson Aug. 17-, 1943 2,475,770 Wijsman July 12,1949

